Method of installing nonbreakable crystals in watch bezels



v Feb. 1930. 4 w, P E Q 1,746,965

METHOD OF INSTALLING NONBREAKABLE CRYSTALS IN WATCH BEZELS Filed May 11, 1927 Patented Feb. 11, 1930 warren sr'res PATENT FFICE WILSON E. PORTER, OF NEW HAVEN, CONNECTECU'I, ASSIGNOR TO THE NEW HAVEN CLOCK CO., OF NEJV HAVEN, CONNECTICUT, A CORPORATION METHOD OF INSTALLING NONBREAKABLE CRYSTALS IN VTATCH IBEZELS Application filed May 11,

My invention relates to an improved method of installing non-breakable crystals in watch-bezels, the object being to reduce to the minimum the cost of so installing such crystals, to entirely eliminate the scratching of the outer faces of such crystals in the installing operation, and to produce an article of superior appearance and convenience.

lVith these ends in view, my invention consists in a method of inserting non-breakable crystals into watch-bezels, consisting in forcing a crystal against a rear portion of the bezel itself, whereby the crystal is bowed and placed under tension, in which condition it is snapped into its seat in the bezel from the rear thereof.

My invention further consists in the method characterized as above and in certain other steps as will be hereinafter described and pointed out in the claim.

In the accompanying drawings:

Fig. 1 is a view in central section of a watch-bezel in which a non-breakable crystal has been installed by my improved method;

Fig. 2 is a detached view in inside elevation of the bezel;

Fig. 3 is a face view of a crystal therefor;

Fig. 4 is a sectional view showing a bezelholder, a bezel positioned therein, a crystal centered upon the inner face of the bezel, and a plunger, all in the positions due to them preparatory to bowing the crystal and inserting it into the bezel by a rear-to-front movement with respect thereto, in accordance with my improved method; and

Fig. 5 is a similar view, showing the position of the several parts at the termination of the crystal-installing operation.

In practicing my improved method of installing non-breakable crystals in watch bezels, I employ, as herein shown, a bezel 10 of the usual crowning form provided upon its inner edge with the usual bezel-retainingflange 11, by means of which it is snapped over and retained upon the usual shoulder formed upon the watch-case for the purpose, the said flange being turned inwardly, parallel with the plane of the bezel. The particular form of the body 10, of the bezel, and of the flange 11 thereof, may be varied as de- 1927. Serial No. 190,536.

sired. The bezel, whatever its form in other respects, is provided with a. crystal-installing-flange or skirt 12 extending inwardly from its outer edge, substantially corresponding in diameter to the sight-opening of the bezel and located at substantially a right angle to the plane thereof, though this flange may be flared at its rear end, if desired. As shown, this flange or skirt is provided at its forward end, where it merges into the body of the bezel, with an annular groove 13, V- shaped in cross-section and designed to receive the beveled edge 14: of a crystal 15 made of transparent resilient material, such as celluloid or any other material having corresponding characteristics. Such crystals are now known in the art and to the trade as unbreakable crystals, and will be hereafter so designated in this description and in the claim appended hereto.

The unbreakable crystal 15 is sufiiciently larger in its extreme diameter than the eX- treme diameter of the groove 13 so that, when the crystal has been sprung into domical or concavo-convex form and its diameter reduced, it will be placed under sufficient tenional compression to thereafter assert it- 'self to retain itself in the groove of the bezel,

when snapped into the said groove at the conclusion of the installing operation.

Turiiing now to my improved method of installing such a crystal in such a bezel, the same is placed horizontally by preference in a suitable bezel-holder 16, after which the crystal 15 is centered upon the inner edge of the crystal-installing-flange 12, as shown in Fig. l, and then subjected by a plunger 1'? centered with respect to its center and having its face crowned as at 18, to clownward pressure, whereby the crystal is forced from rear to front with espect to the bezel and thus bowed until it is sufficiently reduced in diameter to permit its bevelled edge 1 to be dragged over the inner edge of the flange 12, after which its said edge will ride over the inner face of the said flange, until it is brought into registration with the annular groove 13, into which the edge of the crystal will then be sharply snapped and seated by the tensional effort of the crystal to resume I its initial flat form. Under this method, the crystal 15 is bowed by the plunger 17 moving in opposition to the bezel itself, or the bezel itself might be moved in opposition to a stationary member corresponding to the plunger 17. In either event, the bezel constitutes one of the two elements required for bowing it, and, in either case, the bowing of the crystal is in the same direction as the movement required to move it into its seat in the bezel.

Under my improved method, it will be observed that the exposed or outer face of the crystal proper is untouched by any tool and so escapes being scratched in the operation of installing it in the bezel, whereas, in the prior art, both faces of the crystal have been engaged during the bowing operation. Moreover, the sight-opening of the bezel is maintained at the maximum, since no stop-flange for the crystal is required, as becomes imperative when the crystal is inserted into the bezel from the front thereof.

Under my invention, by utilizing the bezel itself as one of the two members required for bowing it, I secure ease and rapidity of installation, and hence reduction in the cost of the installing operation. Moreover, the as sembling-fiange serves as a dial-mat and enhances the appearance of the bezel and hence of the watch. While I have described my invention in connection with watch-bezels, it is obvious that it is equally applicable to all bezels designed for instruments having faces or dials requiring the protection of crystals.

I claim A method of installing a non-breakable crystal in a sheet-metal bezel having an inwardly-extending combined crystal-installing flange and dial-mat located at substantially a right angle to its plane and also having near its outer face an annular crystalretaining groove, the said method being characterized by utilizing the bezel itself as one of the complementary bowing-tools and consisting in placing the bezel in a bezel-holder, then positioning a non-breakable crystal directly upon the inner edge of the said flange of the bezel, then subjecting the crystal to pressure by a bowing-tool engaging its central portion and then moving the said bezelholder and bowing-tool, one with respect to the other, whereby the crystal is forced from rear to front with respect to the bezel and caused to assume a domical form, thus reducing its diameter and placing it under tension, so as to be held in place thereby in the bezel when its edge is snapped into the said annular crystal-retaining groove thereof.

In testimony whereof, I have signed this specification.

WVILSON E. PORTER. 

